CO2 capture and sequestration is one of the only feasible means for significantly reducing CO2 emissions from coal-fired power plants. One promising method of carrying out CO2 capture is the use of dry adsorbents in a temperature swing process. Potential sorbents are being invented and evaluated extensively in the industry. One of the most common types of solid adsorbents are those that are functionalized with an amine.
Although sorbents that utilize an amine have demonstrated promising traits related to CO2 capture, the amines will often react with SO2 or other acid gases commonly present in flue gas to form heat stable salts. If the heat stable salt sites cannot be reclaimed or regenerated then the sorbent used in a commercial process will need to be prematurely replaced due to loss of functionality. This could result in significantly increased operational costs for CO2 capture systems. It is commonly not feasible to replace only the sorbent that has formed a significant amount of heat stable salts.
A need therefore exists in the art for an amine-based sorbent having a longer working life cycle, superior degradation characteristics, and/or superior functional site regeneration characteristics.